Hot-Galvanizing a Tacoma frame?

Greetings, Tacoma World!

I'm starting the build of my new 2002 Tacoma Extra-cab 4x4 2.7 Auto with a rusted-through frame. The truck belonged to my dad, and I'd like to give it a second life as a daily driver and light off-roader for Maine winters

I've already purchased an exact replacement frame, which looks brand new. I plan to swap the frame in my driveway, replacing whatever falls apart as I go through it.

I've heard of Land Rover people having their frames hot-dip galvanized to protect from rust long-term. Apparently, the process will coat the inside of box-frames protecting them for a very very long time. Protecting threads and fitted openings on the frame seems important, and I'm not sure what to expect.

Anybody have any experience galvanizing these frames? Anything to watch out for? Should I strengthen the frame with plates before the thing gets dipped?

 

Welcome to TW!

 

@Taco critter

 

I think it’s Volvo that used to do it to all their cars (and maybe still do? Dunno) with really good success. Hot dipped has kinda a ugly surface finish but maybe just spray paint over it? Seems like a cool idea but I’d guess it’ll come down to if you can find a place to do it that won’t be unreasonably expensive

 

You'll want to do any repairs and modifications prior to getting it dipped. That way you don't have to remove the coating and add uncoated metal.
I tried to have my car frame dipped, but they refused to do it for liability reasons.

 

Thanks for the welcome! It's a great forum you all have here, it has already been very useful.

On the modifications before dipping, I was thinking about:

a. welding on pre-fab plate strengtheners on the rear c-channel section- I've heard this area is weak
b. welding on brackets for some kind of home-made tube step
c. Any other known weak spots to address?


The place I'm taking it will dip it for about $300, but recommends it be sandblasted first, bringing the total cost to $600. Overkill? Maybe, but I'm going for long term peace of mind. And the salt in Maine is wicked.

Galvanizing is said to offer superior corrosion resistance because the zinc "sacrifices" before the steel-so in theory, the zinc corrodes away before the steel- protecting even parts of steel that become exposed directly to the elements. And, it'll protect the inside of the frame as completely as the outside.

I've heard if i wait a year for the finish to "weather", it'll take paint easy. And that painting it with fresh zinc is more challenging. But i'm not finding much online from anyone who's done this, so I dunno.

Thanks for your replies!

 

Remember, you'll have to re-tap every threaded hole in it so buy yourself a quality tapping set with all the needed thread sizes.

 

Any thoughts on using sacrificial fasteners cut to length in the threaded holes before dipping? (Then maybe heating them up with a torch and backing them out after the dip) Would they just get zinc-welded in there and snap off?

 

Don't worry about painting it, it's unneeded and the galvanized frame will look fine. Make sure they rotate it and rinse it very well before you start attaching parts to it.

 

I think Audi has hot dip galvanized their chassis to prevent rust since 2001 or earlier.
smart Germans (with snow in their land) would probably be disappointed if their vehicle rusted due to not using technology (what they're known for) to not prevent it.

Toyota on the other hand, I guess just Didn't Give A Shit

It's also a good business strategy to sell cars. Sabotage them so they're designed to fall apart in 10 years, forcing people to buy a crappy new one they don't want for more money, and further pollute Earth with more toxic car parts laying around because of that (mercury leaking from bulbs into the ground, etc.)

supposedly galvanized metal is gnarly to weld. That's one thing to consider given it's a Toyota truck that you'll probably modify in the future such as doing welding on the frame.

 

Anything threaded you put in it will ''grow'' so if you do that, grease the threads [talk to the galvanizer] and only install the bolt until it reaches the end of the threaded hole.

 

Great thought on the rotation I'll ask the galvanizer about greasing threads and post about it.

 

Two great looking first gens! Nice Dodge too. Welcome to TW

 

When I hot dipped my 5x9 utility trailer they acid dipped mine before dipping in the gal. and that's been 20 yrs ago, give or take a few. Still looks like new, but the fastner holes will need to be cleaned for the bolt clearance, this will only apply to the tight tolerance hole's,,, on mine I pre drilled mine about 1/32" before dipping to get the desired effect,,, the threaded holes will have to be tapped again clean more than likely.

It really depends on the dipper, if it goes on thick. I wouldn't worry to much about it if the bolts won't run through just tap them back out clean and coat the threads through and through with never seize or a good grease before running the bolts back through for good.

 

The galvanizing process produces a lot of heat. Have you asked the place that is going to dip it how they handle warping if it happens? Not trying to freak you out but most galvanizing places have a plan to combat warping. Typically galv will weather in 6 months for painting if you choose to do that and can be wiped down with pure white vinegar to help clean the surface before painting.

 

Yea you can give yourself zinc poisoning welding it. So it's either ventilate the area or respirator. I use a badass high zinc primer from duplicolor and gave myself zinc poisoning building a front bumper and making some weld repairs and didnt grind it all off and didn't have my usual fan near by sucking the smoke away from my face. Sucked, feels like a stomach flu, and your lungs hurt, gotta chug a bunch of milk to make it go away.

 

Thanks for the warnings about welding around Zinc! That sounds awful. I'm content leaving this one basically stock for its lifetime, so future welding isn't on the radar (fingers crossed)... the idea i have is to address any weak points/add slider mounts now.

I'm thinking rear frame stiffeners and home-made slider mounting brackets, and anything else you recommend I add/reinforce before the window for welding pretty much closes.

 

Whenever we had any steel hot dipped at work, we sandblasted it first, the gavalize adhered better.

 

Both right but all welders know that welding on galvy is no good. Just takes a bit of extra prep and also make sure there is plenty of ventilation and at work they use certain fans and 'smoke eaten to get the fumes away from welder and everyone else. I went through that shot myself.... no good

 

$600.00 with the Sand Blasting sounds very Cheap.

What thickness will the coating be??

We Have a customer that is an Industrial Galvanizing provider talking one time explained the time in the tank determines the thickness of the coating